The invention relates to devices for monitoring the condition of components, in particular of rotating components of vehicles or machinery. When attempting to monitor the condition, it is often difficult to find suitable locations for the required sensor systems such that they can be applied without disassembly of mechanical systems and resultant destruction of the assemblies and components they are intended to monitor.
Connecting sensors or sensor modules directly to bearings etc. for condition monitoring is often not practical but getting the parameters of interest such as temperature, vibration and acoustic emission to a remote sensor can be difficult.
Sensor systems should be configured such that they can be quickly and easily installed for a range of condition monitoring tasks. However, increased mounting comfort often leads to an increased distance between the sensor system and the component of interest, such that the quality of the measurement is reduced due to attenuation, increased noise and environmental factors.
Parameters measured in condition monitoring are typically vibration, acoustic emission or temperature. The longer the transmission path for heat or acoustic waves, the higher the risk that information gets lost. Maximizing the transmission of signals of interest to the sensor is a key factor in maximizing the signal-to-noise ratio. In particular, material interfaces and components between the sensors and the component of interest should be minimized, as each interface can add significantly to an attenuation of signals. Unavoidable loss due to reflection or absorption at material interfaces may be reduced by matching the acoustic impedances of the materials involved. Further, the sensor system should have a compact design as the space envelope of suitable mounting sites is often small.